1. Field of the Invention
The present invention relates to devices for applying stress to joints and, more particularly, to a knee stress radiography device used to place stress on a knee joint in a desired position, particularly when an X-ray image of a knee is taken.
2. Description of Related Art
Certain diagnostic X-ray examinations of the knee can be made only when the knee is held in a specific position. In order to accurately perform stress radiography of the knee and other joints, applying stress to the knee is required. This requires a person to hold the patient's leg and apply stress to the knee joint, which causes this person to be in close proximity to the X-ray beam. Further, when the person is holding the patient's leg, the stress applied to the knee at one particular time may not be the same stress applied to the knee at a different time, thereby making it difficult to perform reproducible stress radiography of the knee.
A device for holding a patient's leg for stress radiography has been described in U.S. Pat. No. 4,232,681. This device is a leg positioning device for X-ray filming that has a support with which the leg can be fixedly held at two-spaced locations, a pressure element that can apply incremental variable pressure to the leg intermediate these locations and a device for measuring the applied pressure so that the same can be exactly reproduced whenever desired.
However, this prior art device and others similar to this device are bulky, expensive and do not adjust to fit all body sizes or adjust to apply pressure to the knee at multiple locations and, therefore, may not be used each and every time by a physician. Therefore, it is desirable to provide a stress radiography device that is inexpensive, lightweight, adjustable for all body sizes and positions, and easy to assemble in order for a physician to accurately and reproducibly perform stress radiography of the knee and other joints while remaining safely outside the X-ray beam.